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I am reading John M. Lee's book: Introduction to Smooth Manifolds ...
I am focused on Chapter 3: Tangent Vectors ...
I need some help in fully understanding Lee's conversation on computations with tangent vectors and pushforwards ... in particular I need help with an aspect of Lee's exposition of pushforwards in coordinates ... ...
The relevant conversation in Lee is as follows:
In the above text we read:
" ... ... Thus
[itex]F_* \frac{ \partial }{ \partial x^i } |_p = \frac{ \partial F^j }{ \partial x^i } (p) \frac{ \partial }{ \partial y^j } |_{ F(p) } [/itex] ... ... ... ... 3.6In other words, the matrix of [itex]F_*[/itex] in terms of the standard coordinate basis is[itex]\begin{pmatrix} \frac{ \partial F^1 }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^1 }{ \partial x^n } (p) \\ ... & ... & ... & ... \\ ... & ... & ... & ... \\ \frac{ \partial F^m }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^m }{ \partial x^n } (p) \end{pmatrix}
[/itex]... ... ... "
My question is as follows:
How ... exactly ... do we get from equation 3.6 above to the fact that the matrix of \(\displaystyle F_*\) in terms of the standard coordinate basis is [itex]\begin{pmatrix} \frac{ \partial F^1 }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^1 }{ \partial x^n } (p) \\ ... & ... & ... & ... \\ ... & ... & ... & ... \\ \frac{ \partial F^m }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^m }{ \partial x^n } (p) \end{pmatrix}
[/itex]... ... ... ?It looks as if Lee derives [itex](F_*)_{ij} = \frac{ \partial F^j }{ \partial x^i } (p) [/itex] from 3.6 ... but how exactly is this justified ... that is, what are the mechanics of this ... I cannot see it ... can someone please help ... ..Peter*** EDIT ***
It has occurred to me that it would be helpful for readers of the post to have access to Lee's definition of pushforwards, and his early remarks on the properties of pushforwards ... ... so I am providing these as follows:
I am focused on Chapter 3: Tangent Vectors ...
I need some help in fully understanding Lee's conversation on computations with tangent vectors and pushforwards ... in particular I need help with an aspect of Lee's exposition of pushforwards in coordinates ... ...
The relevant conversation in Lee is as follows:
" ... ... Thus
[itex]F_* \frac{ \partial }{ \partial x^i } |_p = \frac{ \partial F^j }{ \partial x^i } (p) \frac{ \partial }{ \partial y^j } |_{ F(p) } [/itex] ... ... ... ... 3.6In other words, the matrix of [itex]F_*[/itex] in terms of the standard coordinate basis is[itex]\begin{pmatrix} \frac{ \partial F^1 }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^1 }{ \partial x^n } (p) \\ ... & ... & ... & ... \\ ... & ... & ... & ... \\ \frac{ \partial F^m }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^m }{ \partial x^n } (p) \end{pmatrix}
[/itex]... ... ... "
My question is as follows:
How ... exactly ... do we get from equation 3.6 above to the fact that the matrix of \(\displaystyle F_*\) in terms of the standard coordinate basis is [itex]\begin{pmatrix} \frac{ \partial F^1 }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^1 }{ \partial x^n } (p) \\ ... & ... & ... & ... \\ ... & ... & ... & ... \\ \frac{ \partial F^m }{ \partial x^1 } (p) & ... & ... & \frac{ \partial F^m }{ \partial x^n } (p) \end{pmatrix}
[/itex]... ... ... ?It looks as if Lee derives [itex](F_*)_{ij} = \frac{ \partial F^j }{ \partial x^i } (p) [/itex] from 3.6 ... but how exactly is this justified ... that is, what are the mechanics of this ... I cannot see it ... can someone please help ... ..Peter*** EDIT ***
It has occurred to me that it would be helpful for readers of the post to have access to Lee's definition of pushforwards, and his early remarks on the properties of pushforwards ... ... so I am providing these as follows: